Devices for use in the marking out of building sites



Aug. 26, 19 9 1G. 1'. B;.AKE 3,462,843

DEVICES FOR USE IN THE MARKING OUT OF BUILDING SITES Filed Dec. 16, 1966r z Sheets-Sheet 1 INVf/VTOR By T M .wm 44% we); 5m

1 7 ORNE Y Aug. 26, 1969 I G. T. BLAKE DEVICES FOR USE IN THE'MARKING'OUT OF BUILDING SITES 2 Sheets-Sheet 2 Filed Dec. 16, 1.966

A T RN YS United States Patent 3,462,843 DEVICES FOR USE IN THE MARKINGOUT OF BUILDING SITES George T. Blake, Orchard Dene, Station Road,Padworth, Reading, Berkshire, England Filed Dec. 16, 1966, Ser. No.602,226

Claims priority, application Great Britain, Dec. 30, 1965,

55,207 65 Int. Cl. G01b 3/14, 5/24 U.S. Cl. 33-1 3 Claims ABSTRACT OFTHE DISCLOSURE The invention relates to devices for use in the markingout of building sites.

When marking out building sites it is customary to use optical sightingprocedures to ensure that corners of a marked out region are square.Recently it has been proposed to use for the optical sighting a devicehaving two sighting paths which are accurately disposed at right anglesto each other. These sighting paths may be pro vided by two telescopeshaving their axes at right angles. Such a sighting device is mounted onan adjustable cantilever support from a tripod and has a vertical axiswhich intersects the axes of the telescopes, the vertical axis beingcoincident with the axis of a downwardly extending tube in which a rodis slidably guided. The rod can be fixed in any position relative to thetube by means of a thumbscrew, and has a pointed or cup shaped lowerend.

The lower end of the slide rod provides the actual datum point after thedevice has been properly set up, and this datum point can be marked bymeans of a marker peg placed in the ground in alignment with the saidlower end. However, the position of the marker peg is lost duringsubsequent trenching operations for foundations. -It is thereforecustomary to project outwardly from the conceptual position of themarker peg by a predetermined amount, for example two feet, and to markthese projected positions, so that after trenching, inward projectionallows the original conceptual marker position to be re-established.This projection is a cumbersome procedure and increases the cost insetting up a building site.

The present invention consists in a device for use in the setting up ofbuilding sites by transferring co-ordinates of a corner datum point oftwo arbitrary points spaced apart from said corner datum point andenabling said corner datum point to be re-established when desired, thedevice comprising two rigid arms pivotably connected together at one endand having rigid means mounted on their other ends for engagement withfixing members adapted to be driven into the ground. Each of the rigidarms and its associated rigid engageable means constitutes an assemblywhich is rigid throughout from the pivot point to the engageable means.The arrangement is such that when the pivot point of the two arms is inregister with the corner datum point and the engagement means at theother ends of the arms are engaged with fixing 3,462,843 Patented Aug.26, 1969 members and the fixing members driven into the ground, thedevice can be removed from the fixing members, the corner datum pointbeing re-established by the said pivot point when the device is againengaged with the fixing members.

In order to make the invention clearly understood, reference will now bemade to the accompanying drawings which are given by way of example andin which:

FIG. 1 is a perspective view of a setting up device according to theinvention FIG. 2 is a perspective view of a fixing device shown engagedby an end of an arm of the device of FIG. 1;

FIG. 3 is an elevation view of the fixing device of FIG. 2, to a largerscale than FIG. 2; and

FIG. 4 is a plan view of the setting up device, shown in its position ofuse.

The setting up device has two arms 1 and 2 pivotably connected at oneend by a rivet or bolt 3 which has a spike 4 which can readily bebrought into a position of register with the vertical axis of the knownoptical sighting device mentioned above. At the other end, each arm 1and 2 has a hole 5 flanked by a stop 6 and a lug 7 carrying a thumbscrew8.

Fixing members 9 are provided which are adapted to be driven into theground. The fixing members 9 have shanks 10 over which the arms 1 and 2can engage by means of the holes 5. The shank 10 of each fixing member 9is mounted by a plate 11 which carries spikes 12 for securing the fixingmember in the ground. The thumbscrews 8 enable the arms 1 and 2 to befirmly secured to the shanks 10.

When a corner datum point for a building site has been obtained by useof an optical sighting device or by any other known means, the spike 4of the device of the invention is brought into register with the cornerdatum point, the arms 1 and 2 being spread apart so as to provide areasonably wide base between the holes 5, although it is not necessaryfor the arms 1 and 2 to be at a right angle to each other. The fixingmembers 9 are driven into the ground at points defined by the holes 5and with the two arms of the device held by the two fixing members 9 thespike 4 is thus held fixed. After the fixing members 9 have been driveninto the ground, the device can be removed from the fixing members,leaving the fixing members remaining in the ground. When it is againdesired to re-establish the corner datum point, it is simply necessaryto re-apply the device to the fixing members, whereupon the spike 4 willagain be disposed in alignment with the corner datum point.

Since the fixing members 9 are disposed at some distance, for exampletwo feet, from the corner datum point, trenching of the site can readilybe effected after the device is removed from the fixing members 9. Ifdesider, the fixing members 9 can be driven into the ground to such anextent that they are below ground level, whereby a trenching machine canrun over them without dislodging them.

I claim:

1. A device for use in the setting up of building sites by transferringco-ordinates of a corner datum point of two arbitrary points spacedapart from said corner datum point and enabling said corner datum pointto be reestablished when desired, said device comprising two fixingmembers adapted to be driven into the ground; two rigid arms pivotablyconnected together at one end at a pivot point; and rigid engageablemeans mounted directly on the other end of each arm respectively andbeing detachably engageable with said fixing members, each of said rigidarms and its associated rigid engageable means mounted thereonconstituting an assembly which is rigid throughout from said pivot pointto said engageable means, whereby when said fixing members are driveninto the ground and said pivot point is in register with the cornerdatum point and said engageable means are engaged respectively with saidfixing member, said arms, said pivot point and said engageable means canbe removed together from the fixing members, leaving the fixing membersin the ground, and the corner datum point may be re-established by thesaid pivot point when said engageable means are respectively re-engagedwith the fixing members.

2. A device as defined in claim 1 wherein each of said fixing memberscomprises a shank, and wherein each arm at its said other end comprisesmeans defining an aperture for engaging over the shank of the respectivefixing member, each said other end having stop means flanking saidaperture for engaging against the associated shank and means flankingsaid aperture and carrying a thumbscrew disposed opposite said stopmeans, said thumbscrew serving for engaging the shank and thusestablishing a firm connection between said arm and the respective 20fixing member.

3. A device as defined in claim 2, wherein each of said fixing memberscomprises a plate through which the said shank extends, and a pluralityof spikes extending from said plate for engaging in the ground.

References Cited UNITED STATES PATENTS 1,313,432 8/1919 Walker 33752,612,695 10/1952 Schneider et a1 3385 2,806,289 9/ 1957 Rongaus et a1.2,835,036 5/1958 Peresenyi. 3,066,416 12/1962 Gutting.

FOREIGN PATENTS 1,073,756 I/ 1960 Germany.

700,207 11/ 1952 Great Britain.

WILLIAM D. MARTIN, JR., Primary Examiner US. Cl. X.R. 33-75

